Chapter 1 Methods in Nutrition Research Flashcards
What are epidemiological studies?
Epidemiology is the study of incidence, distribution, control and prevention of diseases.
These studies are sometimes referred to as observational as they are based on observing relationship rather than on experimental testing.
What are cohort studies?
AKA prospective, longitudinal or panel studies.
Purpose is to explain why certain individuals within a population suffer from certain diseases.
These studies are highly flexible, utilitarian and informative research design.
Need to recruit large number subjects (30 000-100 000 or more). Data is obtained over a long period of time (5 to 20 years) so that a sufficient number of subjects have developed the disease.
What are case control studies?
Purpose is to explain why certain individuals within a population suffer from certain diseases (like cohort studies).
There is a direct comparison made between healthy subjects and people that already have the disease.
Recruit 50-500 people are recruited.
Downside of these studies: “the healthy volunteer effect” and “recall bias”
What are cross-sectional studies?
This type of study is designed to be a snapshot in time.
Can investigate conditions that are either present or absent.
These studies are often used to determine such things as BMI and BP
What are population studies?
AKA ecological studies.
typically two dozen or more countries are compared.
Sources of error: disease stats are unreliable esp in poor countries, also food consumption data unreliable–in rich countries lots of food is wasted.
What are historical studies?
the relationship between nutritional patterns and changing disease rates often provides clues.
What are randomized clinical trials?
Referred to as the gold standard.
single pool of participants is selected who would potentially benefit from an intervention: randomized into intervened and control groups.
